The University of Sydney Nano Institute team
University science is behind some of the most profound innovations and breakthroughs in water research, from the development of cutting-edge techniques to maximise irrigation, to the creation of innovative new materials that can literally capture water from the air.
At the University of Sydney, the Advanced Capture of Water from the Atmosphere (ACWA) project applies nanoscale materials science to mimic the remarkable adaptation of desert beetles in Namibia, a region where just 1.4cm of rain falls each year. The beetle collects water vapour from the atmosphere, turning it into liquid via the intricate shapes of tiny bumps on its exoskeleton.
Biomimicry — learning from, and mimicking, clever strategies found in nature to solve human design challenges — is an important component of the work of the University of Sydney Nano Institute, co-led by chemist Professor Chiara Neto and physicist Professor Martijn de Sterke. Innovations from the research include a nanotextured surface which can repel bacteria, algae and other marine life from ships’ hulls, inspired by a lotus leaf; a nanoscale slippery surface, inspired by the pitcher plant, that can be used for microfluidic channels in bioengineering; and a stain-resistant paint base.
The Institute has attracted top-level researchers from chemistry, physics, materials science and bioengineering from across the university.
“We began with the idea of capturing water from the atmosphere by optimising the surface chemistry of a material so it would enable the formation of droplets out of humid air,” says Neto.
“We are now developing new devices that capture water from the atmosphere through condensation, using no external source of energy, by designing surfaces that spontaneously cool when exposed to the air,” she says.
Related: Software saves rainwater
The team has made two key breakthroughs. First, they have perfected the surface science of nanoscale ‘bumps’ shaped in a way to harvest a very thin film of water vapour, similar to the Namibian desert beetle.
Their second breakthrough is the development of an entirely new surface that is naturally chilled and causes water to condense into droplets. Wherever the atmosphere is above 30% humidity, this surface will automatically collect water vapour from the air.
The ACWA project is well on the way towards its ambitious goal to create materials that capture sufficient water from the atmosphere to alleviate the effect of drought by providing water for humans, animals and plants.
Patents are underway for exciting applications for the technology, including watering devices to use within greenhouses; a portable self-filling water bottle for bushwalkers and emergency crews; and small water stations to sustain wildlife in remote areas
— Fran Molloy
This article appears in Australian University Science issue 2.